Some of the conventional desk-top calculators, like for example a scientific electronic calculator for scientific calculations, are arranged such that constants stored anteriorly, universal gravitation constant, gas constant and the like, may be accessed for calculation uses whenever occasion calls.
Such a desk-top calculator is provided for example with a CNST key, as a constant access key. Each time the CNST key is operated, the different types of constants stored in the desk-top calculator are accessed successively and displayed, as shown in the following Table 1. That is to say that the desired constant used to be accessed by operating the CNST key an appropriate number of times.
TABLE 1 ______________________________________ Operation Operation Displayed Display order key constant contents ______________________________________ 1 CNST c:light c = 2.99792458.sup.08 .sup. velocity 2 CNST G:universal G = 6.67259.sup.-11 .sup. gravitation .sup. constant . . . .sup. . . . . .sup. . . . . .sup. . n CNST R:gas constant R = 8.31451 ______________________________________
Also, some of the conventional desk-top calculators, for example as shown in FIG. 4, are arranged such that, they are provided with a shift key 13, and use the numeric keys 11 both as keys for entering numeric values and as keys for accessing constants. Thus the desired constant is accessed by operating the shift key 13 and a numeric key 11 in combination.
In this type of desk-top calculator, for example the gas constant R used to be accessed by operating the shift key 13 and the key 12 of the numeric value "5", successively.
However, in the conventional desk-top calculator provided with a CNST key described above, in order to access a constant, the CNST key always needs to be operated a determined number of times corresponding to each constant.
Also, in the desk-top calculator provided with the shift key 13, two keys, i.e. the shift key 13 and a numeric key 11, need to be operated each time a constant is being accessed.
Accordingly, a conventional desk-top calculator used to present the problem that its operation tended to be complicated. Especially when accessing constants frequently, the operation efficiency of a conventional desk-top calculator was extremely low.